The invention is in the field of the use of ultrasonic devices for the treatment of keratinous fibers with a chelant.
Bleaching and dyeing keratinous fibers, such as hair, has become increasingly popular. This technology enables people to change the natural color of a fiber to a potentially more fashionable color, or to conceal imperfections present within a natural fiber. However, these methods are slow, laborious, ineffective, not topically efficacious, and the chemical agents used can damage the treated fiber.
In these processes, the desired color is produced by chemically treating the naturally produced fiber pigment, melanin. Melanin is formed in a hair bulb at the root of the hair and deposited into the central part of the hair shaft, as the hair grows. The hair shaft, which has two major regions (the cuticle region (exterior) and a cortex region (interior)), comprises dead cells that have differentiated into a mixture of different forms of the hair protein, keratin. Keratin within the cuticle region, contains high concentrations of the amino acid cystine. Each cystine molecule comprises two cystine amino acids cross-linked by a disulfide bond that provides the cuticle with most of its hydrophobic properties, physical durability, and stability to swelling. The cuticle is a protective layer for the hair, preserving the integrity of the cortex. The cortex provides rigidity and most of the mechanical properties to the hair fiber.
A typical hair lightening process achieves a lightening effect by oxidation of the melanin pigments using bleaches. Bleaches typically comprise an oxidizing agent in an alkaline solution. Typical oxidizing agents are hydrogen peroxide, potassium, sodium, or ammonium salts of perborate or percarbonate, persulfate, and percarbamate.
The traditional permanent coloring process utilizes permanent, or oxidative, dyes consisting of small molecules capable of diffusion into the hair fiber. Typically, these molecules belong to three classes of aromatic compounds: diamines, aminophenols, and phenols. The small size of these molecules facilitates diffusion into the hair shaft where they are activated by an oxidative material to form a larger colored complex within the hair shaft.
However, these oxidative treatments have several drawbacks. First, effective bleaching and dyeing processes damage hair due to the aggressive and chemically indiscriminate nature of the oxidizing agents. The oxidizing agent penetrates and damages the cuticle en-route to the cortex, where melanin oxidation occurs. This damage is particularly exacerbated by repeated use of high pH oxidation treatment compositions. Repeated treatments destroy the keratin disulfide bonds resulting in cuticle degradation and subsequent cortex damage resulting in decreased fiber strength and weak, brittle hair. Thus, the capability of the composition to produce desired cosmetic changes such as light shade, color evenness, color fading, general hair feel, shine, and/or luster is decreased.
Chelants can be applied to a keratinous fiber to remove, mask, or inactivate bound minerals. Removing these minerals can lessen visible fiber damage. The effectiveness of a chelant is primarily a function of the rate of penetration of the chelant into the fiber. A typical chelant-based treatment comprises a step where a hair fiber is contacted with a blend of chelating agents at a concentration of 4 to 25 percent w/w and a pH ranging between 4 and 10.
Additionally, devices incorporating ultrasonic mechanical vibrations are well known in the art. Ultrasonic mechanical vibrations are generally produced by Piezoelectric devices. Piezoelectric devices convert electrical impulses into mechanical vibrations by developing a mechanical motion by deforming certain crystals under pressure. Resonant crystals and ceramics are used to generate such mechanical waves in solids and liquids. For high frequency, ultra-sonic vibrations to be generated, crystals operate in their thickness mode (the crystal becomes alternatingly thicker and thinner as it vibrates.)
While the materials described are suitable for bleaching or dying a hair fiber, the nature of the process by which a fiber is dyed can be process sensitive. For example, the maximum speed at which such treatment occurs can be limited by the effectiveness of the chelant molecule, the treatment time, the rigor of the treatment, and/or the concentration of chelant in the compound. Accordingly, it would be desirable to provide an improved process suitable to treat fibers with a chelant. It is desirable to reduce the deleterious effects described above. It would be an improvement in the art to provide a novel process to treat a keratinous fiber, such as hair, using less chemical agent, and provide a faster, less labor intensive, and more topically efficacious treatment experience.
In a non-limiting exemplary embodiment of the present invention, the process for the oxidative treatment of keratinous fibers comprises placing a chelant proximate to a keratinous fiber and placing an ultrasonic treatment device proximate to the keratinous fiber. The ultrasonic treatment device is energized to produce a topically efficacious energy. The topically efficacious energy is applied from the ultrasonic treatment device to the keratinous fibers so that the topically efficacious energy efficaciously deposits the chelant onto the keratinous fiber.
In yet another alternative embodiment of the present invention, the process for the oxidative treatment of keratinous fibers comprises providing an ultrasonic treatment device comprising a comb device, a first material reservoir for supplying a first material, a second material reservoir for supplying a second material so that the first material reservoir and the second material reservoir are in liquid communication with the comb device. At least one of the first material or the second material is dispensed from the ultrasonic treatment device onto the keratinous fibers. The ultrasonic treatment device is energized to produce a topically efficacious energy. The topically efficacious energy is applied from the ultrasonic treatment device to the keratinous fibers.
In yet another embodiment of the present invention, a kit comprising at least one chelant and at least one active agent combined in a container is provided for the oxidative treatment of keratinous fibers.